In vivo studies of HDL assembly and metabolism using adenovirus-mediated transfer of ApoA-I mutants in ApoA-I-deficient mice

Biochemistry. 2001 Nov 13;40(45):13670-80. doi: 10.1021/bi011451e.


We have used adenovirus-mediated gene transfer in apoA-I-deficient (A-I-/-) mice to probe the in vivo assembly and metabolism of HDL using apoA-I variants, focusing primarily on the role of the C-terminal 32 amino acids (helices 9-10). Lipid, lipoprotein, and apoA-I analyses showed that plasma levels of apoA-I and HDL of the mutants were 40-88% lower than that of wild type (WT) human apoA-I despite comparable levels of expression in the liver. WT apoA-I and mutant 1 (P165A, E172A) formed spherical particles with the size and density of HDL2 and HDL3. Mutant 2 (E234A, E235A, K238A, K239A) generated spherical particles with density between HDL2 and HDL3. Mutant 3 (L211V, L214V, L218V, L219V) and mutant 4 (L222K, F225K, F229K), which have substitutions of hydrophobic residues in the C-terminus, generated discoidal HDL particles indicating a defect in their conversion to mature spherical HDL. Significant amounts of mutant 4 and mutant 5 (truncated at residue 219) were found in the lipid poor fractions after ultracentrifugation of the plasma (18 and 35%, respectively, of total apoA-I). These findings suggest that hydrophobic residues in and/or between helices 9 and 10 are important for the maturation of HDL in vivo.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adenoviridae / genetics
  • Animals
  • Apolipoprotein A-I / blood
  • Apolipoprotein A-I / deficiency
  • Apolipoprotein A-I / genetics
  • Apolipoprotein A-I / metabolism*
  • Cholesterol, HDL / blood
  • Dimyristoylphosphatidylcholine / metabolism
  • Gene Deletion
  • Gene Transfer Techniques
  • Genetic Vectors
  • Humans
  • Lipids / blood
  • Lipoproteins, HDL / blood
  • Lipoproteins, HDL / metabolism*
  • Liver / metabolism*
  • Male
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Mutation
  • Phosphatidylcholine-Sterol O-Acyltransferase / metabolism
  • Protein Structure, Secondary
  • RNA, Messenger / metabolism


  • Apolipoprotein A-I
  • Cholesterol, HDL
  • Lipids
  • Lipoproteins, HDL
  • RNA, Messenger
  • Phosphatidylcholine-Sterol O-Acyltransferase
  • Dimyristoylphosphatidylcholine